Stirring device

ABSTRACT

A device for stirring liquid contained in a bung-type drum, the stirring action being generated by a shaft-mounted rotor having vanes retractable into a configuration permitting insertion of the rotor through the bung with the shaft.

PATENTH} FEB 21974 mvsmons Bruno E. Enssle BY Jerry P. Malec Fly. 5

. ATTORNEY STIRRING DEVICE BACKGROUND It is common practice to storepaints and other liquid materials in relatively large drums, and storagefor any length of time immediately creates a problem of restoring thesuspension of solid materials, such as pigments that settle out. Smallcontainers can be handled conveniently in shaking devices which generateenough circulation of the liquid within the drum to restore suspension.In the case of large drums, however, the shaking equipment becomesprohibitively large and costly, and also involves handling proceduresthat become a nuisance. These problems have tended to cause liquidshaving a settle-out problem to be stored in containers that have anentire end removable. This arrangement permits the insertion of mixingdevices and agitators functioning on the same general principle as amalted-milk mixer in a drug store.

There are a number of advantages, however, to handling liquids inbung-type containers, particularly when large quantities of material areinvolved. In the case of paints, it is undesirable to expose the surfaceof the liquid to air any more than is absolutely necessary. Theformation of surface skin on a container of paint is very troublesome,and unnecessary exposure of the paint also creates a vapor problemwithin the work area.

SUMMARY OF THE INVENTION The present invention permits the use of largebung-type drums for storing liquids containing suspended solids, withoutinterfering with the possibility of stirring the liquid to restore thesuspended condition. A stirring action is provided by a rotor mounted ona shaft driven by any convenient form of portable motor unit, with therotor having preferably a group of retractable vanes that can be placedin a position permitting insertion of the entire rotor through the bungopening, followed by extension of the vanes into operating position bythe effect of centrifugal force, or by dynamic forces generated withinthe liquid through movement of the rotor.

DESCRIPTION OF THE DRAWING The several features of the invention will beanalyzed in detail through a discussion of the particular embodimentillustrated in the drawing. In the drawing:

FIG. 1 is a perspective view showing a workman using the stirring devicein a standard bung-type drum of liquid.

FIG. 2 is a perspective view on an enlarged scale, showing the rotor andshaft of the stirring device, with the vanes in the extended position.

FIG. 3 is a view of the device shown in FIG. 2, with the vanes in theretracted position.

FIG. 4 is a cross section through the axis of the rotor showing theconfiguration of the vanes and the hub for establishing the interactingstops defining the extended position of the vanes.

FIG. 5 is a perspective view on an enlarged scale, showing the rotorvane separately.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a standarddrum has a bung opening 11 through which the stirring device has beeninserted. The shaft 12 is driven by the conventional air motor 13 heldin the workmans hand, and supplied with compressed air through theconduit 14. During the operation of the device, the shaft 12 rotateswithin the bung opening 11.

The primary stirring action is generated by the device in the positionin which it appears in FIG. 2. The hub 15 is mounted on the shaft 12,possibly with the assistance of the adapter 16. The set screws 17 and 18secure the hub with respect to the shaft. The hub is provided with agroup of pairs of generally radially-extending lugs l920, 2l22, 23-24,and 25-26. The lugs constituting each pair are spaced apart sufficientlyto receive the radially innermost ends of the vanes 27-30, respectively.These vanes are all formed as shown in FIG. 5. and are provided with theflat inner end portions 28 having the arcuate corner 29 concentric withthe holes 30, which receive pivot pins in the position shown at 31 and32. These pins traverse the pairs of mounting lugs, as well as the holes30, with this mounting permitting limited rotation of the vanes in aplane containing the axis of the shaft 12. When the vanes are extendedfully to the radial position shown in FIG. 2 (and in the position of thevane 29 in FIG. 4), the portion 33 of the vane comes in contact with thefixed structure of the hub, and prevents further swing-out movement ofthe vane 29, as shown in FIG. 4, in a counterclockwise direction. Themovement of the vane from the position of the vane 27 in FIG. 4 to thatof vane 29 can be accomplished by the action of centrifugal force,either separately or in conjunction with a dynamic force created by theinclination of the outer blade section 34 with respect to a planeperpendicular to the axis of the shaft 12. This inclination produces thewell-known propeller action, and the rotation of the shaft 12 by themotor device 13 should be in such a direction as to induce movement ofthe vanes from the FIG. 3 position to the FIG. 2 position. The vanesnormally depend downwardly (in the static condition of the device) tofacilitate insertion into pg,5 the drum, and also to permit withdrawalfrom the drum after the stirring operation has been completed. It isimportant to assure that the direction of folding movement is not suchthat gravity will maintain an extended position of the vanes which wouldblock withdrawal through the bung opening 11.

It is obvious that the use of the propeller action will serve not onlyto extend the vanes, but also to generate a very desirable degree ofcirculation within the liquid in the drum to induce a restoration of thesuspended condition of any solids that may have settled out. If a deviceis carefully handled, it is also possible to use the unit in a slightlymodified manner, in

which the rotor can be forced down into a settled mass of previouslysuspended material, and actually scrape it off the bottom of the drum.If the rotation of the motor 13 is reversed when the rotor device isnear the bottom of the drum, the resulting dynamic forces on the vaneswill tend to move them to the FIG. 3 position. However, the presence ofthe bottom of the container can be determined so as to permit the vanesto follow the bottom surface to produce a desirable scraping action. Theinclination of the vanes under these operating conditions will tend toremove settled mass from the bottom of the container. Cleaning of thedevice after the stirring operation has been completed is an obviouslysimple procedure, since it merely involves immersing the unit in asuitable container of cleaning solution, and rotating it, preferablyeither intermittently, or in opposite directions, to flex the bladesfrom the FIG. 2 to the FIG. 3 position.

The particular embodiments of the present invention which have beenillustrated and discussed herein are for illustrative purposes only andare not to be considered as a limitation upon the scope of the appendedclaims. In these claims, it is our intent to claim the entire inventiondisclosed herein, except as we are limited by the prior art.

We claim:

1. In combination with a drum having a relatively small bung opening, adevice for stirring the contents of said drum comprising:

a shaft insertable in said bung opening;

a hub normally mounted on said shaft, said hub having pairs of generallyradially-extending lugs;

a vane rotatably mounted with respect to said hub between each of thelugs constituting said pairs, respectively, for movement between (a)retracted position in which said hub and vane are together insertable insaid bung opening, and (b) extended position, said vane being induced tomove outwardly and upwardly to extended position by movement of saidshaft, said vanes having the portions thereof which are disposed betweensaid lugs formed to provide a stop engageable with said hub to definethe extended and retracted positions of said vanes, said vanes alsohaving offset portions extending toward the axis of rotation of said hubin said retracted position and occupying the space opposite'th'e end ofsaid huband shaft in said retracted positionfaiidlmeans tbrdfivirig saidshaft.

1. In combination with a drum having a relatively small bung opening, adevice for stirRing the contents of said drum comprising: a shaftinsertable in said bung opening; a hub normally mounted on said shaft,said hub having pairs of generally radially-extending lugs; a vanerotatably mounted with respect to said hub between each of the lugsconstituting said pairs, respectively, for movement between (a)retracted position in which said hub and vane are together insertable insaid bung opening, and (b) extended position, said vane being induced tomove outwardly and upwardly to extended position by movement of saidshaft, said vanes having the portions thereof which are disposed betweensaid lugs formed to provide a stop engageable with said hub to definethe extended and retracted positions of said vanes, said vanes alsohaving offset portions extending toward the axis of rotation of said hubin said retracted position and occupying the space opposite the end ofsaid hub and shaft in said retracted position; and means for drivingsaid shaft.